Electromagnetic speed sensor

Claim 1

APPARATUS FOR SENSING THE SPEED OF A FLUID COMPRISING: A CORE OF MAGNETTIC MATERIAL, SAID CORE HAVING FIRST AND SECOND POLES AT THE ENDS THEREOF, A WINDING ABOUT SAID CORE FOR ENERGIZING SAID CORE AND PRODUCING AN ALTERNATING MAGNETIC FIELD BETWEEN SAID POLES, A WALL OF INSULATING MATERIAL POSITIONED ADJACENT ONE OF SAID POLES WITHIN THE INFLUENCE OF SAID MAGNETIC FIELD, A PLURALITY OF ELECTRODES MOUNTED ON SAID WALL SYMMETRICALLY ABOUT SAID POLE, SAID ELECTRODES BEING WITHIN THE INFLUENCE OF SAID MAGNETIC FIELD AND ADAPTED TO CONTACT SAID FLUID, MEANS FOR CONNECTING TOGETHER OPPOSITE ELECTRODES TO PRODUCE A PLURALITY OF PAIRS OF ELECTRODES, EACH PAIR OF ELECTRODES PRODUCING A SPEED SIGNAL INDICATIVE OF FLUID FLOW SPEED PAST SAID PAIR OF ELECTRODES, SERVO MEANS RESPONSIVE TO SAID SPEED SIGNALS FOR ALIGNING ONE OF SAID PAIRS OF ELECTRODES IN THE DIRECTION OF FLUID FLOW, SAID ALIGNED PAIR OF ELECTRODES PRODUCING AN OUTPUT SIGNAL INDICATIVE OF MAXIMUM FLUID VELOCITY, AND MEANS RESPONSIVE TO SAID SERVO MEANS FOR PRODUCING A SIGNAL INDICATIVE OF FLUID FLOW DIRECTION.